Table 4-37 Mass Flow Prompts - Honeywell VPR100 User Manual

Mass Flow
By compensating for variations in fluid temperature and pressure, Mass Flow is used to obtain a more
precise fluid flow measurement from an orifice plate developing a differential pressure. The output CVn
OV is mass flow and is calculated from the following formula for U.S. Units Of Measurement:
MF = FACTOR 1 x SQRT [DP INPUT x (PRESSURE INPUT+14.7) / (TEMPERATURE INPUT + 459)]
where
FACTOR 1 is calculated by user
DP INPUT is differential pressure in inches of water
PRESSURE INPUT is in PSIG
TEMPERATURE INPUT is in °F
Or, Mass flow is calculated from the following formula for International Units Of Measurement:
MF = FACTOR 1 x .569 x SQRT [DP INPUT x (PRESSURE INPUT +101.4)/(TEMPERATURE INPUT + 273)]
where
FACTOR 1 is calculated by user
DP INPUT is differential pressure in KPASCALS
PRESSURE INPUT is in KPASCALS
TEMPERATURE INPUT is in °C
Table 4-37 describes the Mass Flow prompts. See Table 4-2 for additional prompts.
Prompt
OUT LOW LIMIT
OUT HIGH LIMIT
DP INPUT
PRESSURE INPUT
TEMP INPUT
UNITS OF MEASURE
FACTOR 1
12/00

Table 4-37 Mass Flow Prompts

Range/Selections
OFF or number
OFF, analog parameter,
number
OFF, analog parameter,
number
OFF, analog parameter,
number
US or International
OFF, analog parameter,
number
VPR & VRX – User Manual
Programming Function Blocks and Features
Definition
Displayed output value will be clamped and will flash
when these limits are exceeded.
Differential pressure input
Pressure input in PSIG or KPASCALS
Temperature in C or F.
Units of measure
Flow factor for the particular installation
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